依据弹簧蠕变试验确定岩石流变模型参数的方法

以试验结果为依据,用符合本试验所用岩石试件的力学行为的三元件粘弹性模型为例,分析了在弹簧式蠕变仪上进行蠕变试验时载荷松弛对确定岩石流变力学模型参数的影响,导出了考虑载荷松驰后,模型参数的计算公式及不考虑载荷松弛而产生的误差计算公式。研究表明,载荷松驰仅对模型参数中与时间有关的力学参数有影响,而对与时间无关的力学参数则无影响,而且其影响的程度与试验机刚度、试件尺寸和岩石本身的力学性质有关。

A METHOD FOR DETERMINATION OF RHEOLOGICAL MODEL PARAMETERS USING EXPERIMENTAL DATA ON SPRING--TYPE CREEP EQUIPMENT

Based on experimental data,a viscoelastic mechanical model consisting of three components ac- cords with the mechanical behaviour of rock sample used in creep test. Taking this model for example, we analyse the influences of load relaxation on determining rheological model parameters of rock sam- ple when creep test is made on spring-type creep equipment. The formulas of calculation of thses pa- rameters are derived,when load relaxation is taken into consideration. and the formulas of calculation of the errors of these parameters, without taking load relaxation into consideration, are also deduced. Result shows that load relaxation only affects time-dependent model parameters and doesn't affect time-independent model parameter. The degree of influence depends on the stiffness of the creep equipment,the sample size and the mechanical properties of rock.